In the conventional sewing machines for sewing quilts, there has been known a machine of a structure such that a bed for supporting a quilt is provided to a frame to be movable laterally, and forwards and backwards whereby the supporting bed is moved relative to the sewing machine body which is under operation to thereby sew the quilt. This sewing machine is of a system in which a quilt is moved relative to the sewing machine body, and hence has a disadvantage in that it needs a very wide floor space more than two times in each of length and width as large as the quilt. In order to overcome such disadvantage the applicant of this invention developed a sewing machine constructed so as to move the sewing machine relative to the quilt secured in position. (Japanese Patent Publication for Opposition Purpose No. 56-8638)
The above-described improved sewing machine has advantages in that it need less floor space, in that it consumes less energy, and in that the sewing operation is performed more speedily and precisely since adverse effects due to inertia are reduced. In this sewing machine, the sewing machine body is mounted to a frame, which is movable forwards and backwards, so as to be laterally movable, and a driving force is transmitted from a motor mounted on the frame to the sewing machine body through a timing belt and the like laterally extended, and hence it has a disadvantage in that it cannot perform a desired zigzag sewing since the driving of the sewing machine body is affected by the lateral movement of that sewing machine body.
Accordingly, it is an object to provide a sewing machine for quilts and the like which is capable of precisely performing zigzag sewing.